The present invention relates to a recording/playback apparatus and an editing method, which are used for editing groups recorded on a disc for recording groups each consisting of a plurality of programs.
In recent years, media that can be used for recording various kinds of AV (audio and video) data and allows the data to be played back has been becoming popular in a wide range of applications.
In addition, also in recent years, promotion to increase the storage capacity of various kinds of media has been going on. Thus, the size of data that can be recorded in a medium can now be increased. Furthermore, with progress made in technologies for compression of data, the storage capacity of a recording medium can also be increased.
By the way, in accordance with a format of ordinary digital audio data used in a conventional apparatus, recorded data is managed in units each referred to as a program. That is to say, in the case of audio data, for example, a program normally represents a piece of music. Thus, recorded data is managed in musical units.
Typical digital audio equipment for handling such audio data includes a mini-disc recording/playback apparatus used in conjunction with an magneto-optical disc serving as a recording medium.
In the case of a mini disc, for example, management information referred to as a user TOC (Table of Contents) abbreviated hereafter to a U-TOC is recorded on the mini disc separately from main data such as musical data. The U-TOC is used for managing already-recorded-data areas and recordable-data free areas. An already-recorded-data area is an area already used by the user for recording main data, and a recordable-data free area is an area in which no data has been recorded. A recording apparatus identifies a recordable-data free area for recording data while a playback apparatus identifies an already-recorded-data area from which data is to be played back.
Every recorded piece of music is managed by using the U-TOC in data units each referred to as a track. The U-TOC includes start and end addresses of each piece of music. Free areas in which no data is not recorded yet are each treated as a recordable-data area, start and end addresses of which, are also cataloged in the U-TOC.
In addition, by managing areas on the disc through the use of such a U-TOC, various kinds of processing can be carried out with ease and at a high speed by merely updating and rewriting information stored in the U-TOC. Examples of the processing are division of a track used as a unit of recorded data such as musical data, combination of tracks, moving of a track (or changing the number of a track) and erasure of a track.
Furthermore, the U-TOC includes an area for recording the title of the disc (or the name of the disc) and a music name (or the name of a track) of each recorded program such as a piece of music as character information. Thus, the user is capable of doing editing work such as work to enter the name of the disc or the name of a track by carrying out an operation.
It should be noted that, in this specification, the technical term ‘program’ is used to imply a unit of typically audio data such as musical data which is recorded on the disc as main data. The technical term ‘track’ may be used to mean the same thing as the program.
In accordance with the format of the conventional mini-disc system, the data recording capacity is 140 MB. Such a capacity can be used for recording compressed, audio data completing an encoding process based on an audio-data compression technique known as ATRAC (Adaptive Transform Acoustic Coding). This data recording capacity of a mini disc for recording such audio data corresponds to a playback time of about 74 minutes.
Then, in recent years, a new format of the mini disc has been developed to achieve a very high recording capacity. In accordance with this new format, by prescribing a disc format and a data format separately, for example, a data recording capacity of 650 MB can be realized. Such a capacity can be used for recording compressed audio data completing an encoding process based on, for example, another audio-data compression technique known as ATRAC2. The ATRAC2 compression technique is a compression technique with a data compression rate higher than its predecessor, namely, ATRAC. This data recording capacity of a mini disc for recording ATRAC2-compressed audio data corresponds to a playback time of about 10 hours.
To put it in more detail, the mini disc with a data recording capacity of 140 MB can be normally used for recording 10 to 20 pieces of music, that is, the number of tracks or the number of musical pieces that can be recorded on such a mini disc is in the range of 10 to 20. In other words, the mini disc can be used for recording about as many tracks as those of the so-called album.
With the data recording capacity of a mini disc increased to 650 MB to give a higher disc recording density and with progress in technology of compressing audio data, the number of tracks or the number of musical pieces that can be recorded on such a mini disc rises. For example, a playback time of about 10 hours can thus be realized as described above. If the playback time of a piece of music is about 4 minutes, for example, about 150 pieces of music can be recorded. By assuming that a playback time of a CD is 74 minutes, a mini disc with a data recording capacity of 650 MB can be used for recording pieces of music recorded on about 8 CDs.
Consider for example that the data recording capacity of a mini disc has been increased to allow more tracks to be recorded thereon as described above. In this case, the user may desire that a number of tracks recorded on such a mini disc be managed in groups which are each typically an album or a unit based on another arbitrary concept.
If the method of management by track units using the conventional U-TOC described earlier is adopted, however, it will be impossible to implement segmentation management by group units cited above as processing carried out by an apparatus. For this reason, in order to manage numerous pieces of music in group units, the user must record the name of each piece of music on typically a label or must remember the track names. As a result, the management of the tracks unavoidably becomes cumbersome and improper.
In addition, a group obtained as a result of the track classification done by the user as described above cannot be selected fast from numerous pieces of music or a number of tracks recorded on the disc. As a solution to this problem, there has been developed an apparatus whereby the beginning of a predetermined number of tracks such as 10 tracks or 10 pieces of music is detected. In the case of such an apparatus, however, the beginning of a group obtained as a result of the track classification done by the user cannot be detected. Thus, the apparatus cannot be said to be an apparatus offering an effective solution to the problem.
Furthermore, if the user desires to carry out a variety of editing works described above in group units, the editing operations will be extremely complicated and troublesome due to the fact that operations to carry out the editing work are performed in track units.